Block copolymers (BCPs) have been used to prepare highly ordered nanoscale domains upon self-assembly and can be utilized in the “bottom-up” fabrication of nanoengineered materials and devices. The molecular characteristics of block copolymers dictate the self-assembly process and are critical in the formation of well-defined nanostructures. Thermodynamic immiscibility between these chemically distinct blocks leads to a variety of ordered nanostructures with periodicity at the scale of 5-100 nm. These microphase separated structures are mostly dictated by three experimental parameters: the degree of polymerization (N), the volume fraction of the blocks (f), and the Flory-Huggins interaction parameter (χ). The chemical nature of the block segments determines χ, which in turn describes the segment-segment interactions. The emerging role of block copolymer lithography in the fabrication of various devices has led to significant challenges in the creation of small features with a high degree of order. Smaller feature size, uniform porous films, faster processing time, and long-range order are a few of the main requirements demanded by the nanotechnology industry as outlined in the International Technology Roadmap for Semiconductors. The feature sizes of self-assembled nanodomains is directly influenced by both the χ and molecular weight of block copolymers. Therefore, decreasing the molecular weight N would reduce feature sizes. However, there is a limit as to how low the molecular weight a linear block copolymer for a given copolymer system can be, before it passes the order-disorder transition (ODT) and is incapable of forming microphase separated assemblies. Equally, block copolymer systems with a high χ can utilize lower molecular weight polymers before the ODT is reached. However, during the annealing phase, film instability occurs due to limited polymer chain entanglement. Long-range ordering in thin films has been achieved with A-B, A-B-A, A-B-C, or A-B/B′-C block copolymers. However, for all linear block copolymers, there exists vast film dewetting during annealing of low molecular weight systems.